The invention discloses a high-efficiency machine part paint spraying machine. The high-efficiency machine part paint spraying machine comprises a machine body, wherein the bottom of the machine body is fixedly connected with supporting legs, a transverse plate is fixedly arranged between the supporting legs, a motor is fixedly arranged on the top of the transverse plate, the output end of the motor is in transmission connection with a conveyor belt, one end of the conveyor belt penetrates the machine body and extends to the top of the machine body, and the part, outside the top of the machine body, of the conveyor belt is in transmission connection with a rotating shaft. The high-efficiency machine part paint spraying machine is provided with the motor, a sliding block and a threaded rod, the motor is started to drive the conveyor belt to rotate, then, the rotating shaft is driven to rotate, a rotating wheel is driven to rotate, nuts are put on a fixing pate, the sliding bock is enabled to slide on a sliding rail till the nuts are clamped, then, the threaded rod is rotated to fix the position of the sliding block, the nuts are fixed, the six nuts can be put on the rotating wheel at the same time, an air compressor is turned on, paint is sprayed to the nuts, as the nuts do circumferential movement on the rotating wheel, uniformity of paint spraying can be guaranteed, and the efficiency of the paint spraying machine is improved.